With the rapid growth of Internet data, database as a storage medium for the Internet data bears increasingly more responsibility for data storage and data access. In a distributed data storage system, a given piece of data has multiple backups and is stored on different servers. Data consistency is an important indicator of Internet services. Data consistency, that is, multiple backups of the given data remain consistent.
In the data consistency protocol adopted in the existing distributed data storage schemas, data write is considered to be successful when data is written to more than a half of the servers. However, the server resource in the cluster is limited, and data consistency occupies considerable server resource, resulting in lower service availability, which is not conducive to efficient processing of service requests.